Effect Of Electron Absorption On Poxy/Phenol Ring-opening Reaction And Application In Latent Epoxy Curing System

At present,the two-component epoxy resin adhesives have a bonding failure rate of more than 70%during use,in order to effectively avoid the problem that the two components are difficult to store and the bonding failure occurs due to the on-site mixing process during the assembly line operation,It has made more sense to develop a new one-component epoxy adhesive system.The dicyandiamide which is cured by the phase transition mechanism is a curing agent commonly used in one-component epoxy adhesives,but the problems of high curing temperature and poor compatibility have been existing.In this study,a series of meaningful results were obtained on the basis of the effect of electron-withdrawing effect on the epoxy-phenolic hydroxyl ring-opening addition reaction,which has reference significance for the study of new one-component epoxy adhesives.1.Glycidyl ether with a yield of more than 90%were used as the matrix resin,and bisphenol compounds with different electron withdrawing groups were used as curing agents to design different epoxy resin adhesive systems.The bisphenol compound having an electron withdrawing group can be obtained by a DSC curing exothermic curve to lower the ring opening reaction temperature of the epoxy/phenol.2.The latent promoter SH-A95 was added to the system,and the addition of the accelerator by the DSC curing exotherm curve can effectively reduce the ring-opening reaction temperature of the epoxy-phenolic hydroxyl group;compare the curing kinetics of the research system;use Kissinger and the Advanced conversion method calculates Ea separately;the activation energy obtained by the higher conversion method further calculates n,m and A.In addition,the SB(m,n)model is a good description of the nonisothermal curing behavior of the system.3.The reaction rate constant and activation entropy,real-time infrared tracking and gel time were used to study the curing reaction activity.The tensile strength,shear strength,thermal stability and storage stability were prepared.One-component epoxy resin adhesive.